Light emitter devices, which include light emitting devices (“LEDs”), are solid state devices that convert electrical energy into light. LEDs can be utilized in light emitter devices or components for providing different colors and patterns of light useful in various lighting and optoelectronic applications. One such application is the use of LEDs in video screens. LED video displays typically comprise arrays of red, green, and blue LEDs mounted on a single electronic device attached to a printed circuit board (PCB) that controls the output of each electronic device.
Conventional LED arrays often have a transparent encapsulant covering the individual LEDs to protect the devices and maximize the efficiency of the devices. When used in applications such as video screens, it may be additionally desirable to reduce and/or enhance the amount of reflected light. Controlling the amount of reflected light can provide benefits such as increased contrast, image sharpness, and consistent color quality across viewing angles.
Additionally, LED devices, such as video screens, continue to increase in size and resolution (e.g., pixel density), while the size of the individual components making up these devices has been decreasing. Accordingly, the time and complexity required to construct these higher resolution devices has necessarily been increasing. In fact, with so-called “8K” displays, which have a resolution of 7680×4320 pixels (e.g., 33,177,600 individual pixels), beginning to gain a foothold in the marketplace, the use of LED (e.g., so-called mini or micro LED) technology to create each of the pixels would require the placement of individual LED components to create the more than 33 million individual pixels via a die attach process. In fact, some such displays require, in order to produce accurate color rendering, three separate LEDs that are each individually controllable for each pixel. In such instances, the three LEDs will comprise a first LED to produce a red-tinted light, a second LED to produce a green-tinted light, and a third LED to produce a blue-tinted light. As such, it may, in some instances, be required for approximately 100 million LEDs to be placed in order to create even a single 8K video display using such mini-LED or micro-LED technology.
Typical mechanical die attach machines can cost approximately $150,000 or more and process only a single light emitter at a time, such devices being capable of processing approximately 3,000 light emitter devices per hour. Not only does the cost of such machines add significantly to the cost of such an 8K display, but the relatively low throughput renders the creation of even a single 8K display impractical. In fact, it would take such a conventional mechanical die attach machine approximately 460 days of continuous, uninterrupted operation to manufacture a single 8K LED display device; this is obviously not economically viable over a long time frame, where cost is expected to be dramatically reduced over time. There are other direct attach tools that have recently become commercially available that are capable of processing approximately 20,000 light emitter device per hour, but the problem of excessively long processing time to manufacture even a single 8K display remains, with such higher throughput machines being capable of producing a single 8K LED display approximately every 69 days, assuming continuous and uninterrupted operation during this time span. As such, a need exists to improve the speed of LED component placement in such high resolution display devices, while maintaining desired light output features and controlling costs.